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By M. E. Kukura, L. G. Stevens

As described in a previous presentation and in various patents, the Minerals Sciences Div. of UOP, Inc., has developed a modified reduction roast ammonia leach process for nickel laterites. This process gave considerable improvement in extraction over the conventional Caron approach as practiced in Cuba, Australia, and the Philippines. This greatly improved response was obtained with a wide variety of ores. This paper describes the pilot plant flowsheet and reviews the design features unique to the UOP process. Operating results from pilot plant campaigns are compared with bench scale results. Operating problems and their solutions are also discussed.

Jan 1, 1976

By Harrison Schmitt

IN the practice of ore finding the geologist is continually confronted with the question of oreshoot extension, so that the general problem seems worthy of systematic investigation. This problem appears when the reserves are estimated and when the advisability of deepening the shaft comes up. Moreover, there is need for lower development cost to keep pace with cost reductions in other departments, or even to offset a rising cost of ore finding or ore following. This can be gained by close geologic control of the development; and much of the geology involved is that bearing on the downward, upward, and horizontal extensions of shoots. Furthermore, the purchase of a mine or prospect often depends directly on the question of shoot extension; because it is seldom that the ore is fully developed and the purchase price is almost invariably based largely on "possible" and geologically prospective ore. Most current methods for estimating '(possible" and the more nebulous classes of ore are crude and indecisive. In the following pages the extension of oreshoots is the major theme, although the more basic subject, the general art of ore finding, is given some space. (A) Direct Methods of Extension Prediction (I) Extrapolation and Interpolation of Shoots by Use of Conventional Geologic and Assay Plans, Projections and Cross-sections There is little need for stressing the desirability of detailed geologic plans, assay plans, projections, and cross-sections as a basis for the study and extension prediction of shoots. Underground and surface mapping, in most cases, ought to be done in exhaustive detail. All features of obvious bearing should be mapped and it is good practice to record all possible details, some of which may become significant when studied in the ensemble. It should be emphasized that the mapping should be done with an impartial mind, with interpretation reduced to the minimum. The symbols of the map can be made to distinguish observed facts from interpretation.

Jan 1, 1929

By Edmund C. Pechin

THE iron trade of America seems on the point of a new departure. After years of struggling against heavy odds, patient endurance in periods of depression and loss, fears and hopes alternating as failure or success seemed to be the penalty or reward ; wanting in sufficient capital, embarrassed by reason of imperfect knowledge and lack of skilled labor, confronted by a powerful foe-every doubt has at last vanished, physical and mechanical difficulties have been largely overcome, capital has become more abundant and remunerative, the excellence of our product has been everywhere established, - and the peculiarities of American character-pluck, energy, and perseverance -have at last placed the trade upon a foundation so broad and stable that upon it we begin to erect the structure of a world-wide business. Concerning the future of the iron trade in the United States there can be but little doubt. The growing scarcity and constantly increasing cost of raw material in Great Britain, their loss of labor by emigration, the social disturbances among the working-classes, assuming a more threatening attitude on each new outbreak ; the rapidly decreasing value of money, in consequence of the enormous production of gold and silver, combine to forbid any return to former prices, and indicate that a point has been reached beyond which any marked increase of production is improbable. The same causes are operating to a greater or lesser extent upon the Continent. . In the meanwhile the growing wants of humanity are rapidly outstripping these sources of supply. In addition to the steadily increasing foreign and home demand, we find, the world over, the most intense activity everywhere displayed in enterprises requiring

By J. S. Ross

Although the opinion has prevailed for several years that bottoni-hole choking under certain flow conditions should effect an increase in flow efficiencies, the use of bottom-hole chokes until recently has been limited in application mainly because of mechanical difficulties encountered in their construction. Within the past year, however, bottom-hole choking, through the development of a removable type of choke, has been applied successfully under various conditions of flow in many Mid-Continent fields. The observation of these field tests indicates that bottom-hole choking, although not applicable to all flow conditions, has an important place in the operation of oil and gas wells. This paper gives briefly the conclusions drawn from the data obtained from the experiments with this bottom-hole choke under various flow conditions, and a description of the choke and its operation. Purpose of Bottom-hole Choking Since, in a normal well, the velocity with which the column of gas is moving generally has a direct bearing upon the quantity of oil it can lift, probably the main purpose of bottom-hole choking is to accomplish an increase in the velocity of this- rising column, particularly in the lower portion of the tubing string. This it does first, by expansion of the free gas accompanying the oil; next, by liberation and expansion of some of the occluded gas normally carried in the oil to the surface; and lastly, by atomization, which results in a more intimate and uniform mixture of the oil and gas. It is apparent, then, that if this velocity, particularly in the lower portion of the flow string, at a given rate of production, is inefficiently low, owing either to an insufficient supply of gas or to excessive surface choking, and slippage takes place, bottom-hole choking should bring about an increased velocity of the gas and hence an increased lifting capacity. But if the velocity of the column of gas at this same rate of production through a surface choke alone is at or above a velocity necessary to lift the oil efficiently, increasing the velocity by bottom-hole choking would probably serve no useful purpose, other than to steady the flow by the better mixture of oil and gas and to lower delivery pressures.

Jan 1, 1932

By C. T. Van Winkle

MINE fires are always dangerous and are frequently accompanied by loss of life during the period of confusion which is apt to follow their discovery. In metal mines, fires may result from the accidental ignition of some combustible material, or they may be of spontaneous origin resulting from the rapid decomposition of sulphide. They occur frequently enough to demonstrate the need of some special equipment and a general plan for controlling them, in addition to measures for their prevention. Nearly all the large copper mines have had fires, and the methods of fighting them have been well described in recent papers, notably-by C. L. Berrien,1 R.. E. Tally,2 and others in discussion. The Copper Queen mine has many shafts, which are connected by underground workings. The deeper parts are ventilated by fans, but in the shallower portions natural ventilation through numerous connecting raises or shafts is sufficient. There have been several fires in the past few years, of which all are extinguished but one, and that is under control. These notes cover particularly the preparations that are being made-to check a new fire, partially or temporarily, and to facilitate the escape of workmen in the interval before a definite plan of fighting it can be established. A fire may occur in a shaft or station, or in some working father away. In case of fire in an upcast shaft, the gas would escape to the surface and the immediate result would probably not be dangerous to workmen, as they could escape by other shafts. In a downcast shaft, however, the gas would be distributed very rapidly throughout a large portion of the mine, and men might easily be trapped and asphyxiated. A fire in mine workings, drift, raise, or stope, would be dangerous in a degree, but the draft there is likely to be less strong than in a shaft and probably a smaller area would be invaded by the fire gases.

Jan 1, 1918

By E. T. Cox

WHILe engaged, in the year 1856, in determining the oil-bearing properties of some bituminous coals from Western Kentucky, by subjecting them to dry distillation in an iron retort, which held about a pint;, and to the neck of which were attached several bottles, for collecting the carbon oils, and washing and measuring the gas, I observed that there was a very great gain in the weight of coke thus made, over that obtained from the same coal when charred in a platinum crucible, as is usual in the laboratory for making the proximate analysis of coal. It was thought at the time that the increase of coke, by the former mode of treating the coal, was due to the pressure which the retarded gas exerted upon the solid carbon, and the possible fixing of a portion of the carbon from the volatile hydrocarbons. For the purpose of obtaining a more definite idea of the effects of pressure on the coking of coals, a series of experiments were made this spring under my direction, by my assistant, Dr. G. M. Levete. The results are highly instructive and full of interest, since they point out some peculiarities in the nature of bituminous coals which

By R. E. Cech, T. D. Tiemann

It has been shown that hydrogen may be made to serve as a rapid and eflicient reducing agent for Cu, Ni, Co, and Fe sulfides if a scavenging agent for hydrogen sulfide is intimately mixed with the sulfide particles being reduced. Accelerated reduction kinetics are demonstrated for nickel sulfide. Copper, nickel, and cobalt sulfides, when treated at certain temperatures in a combined reducing agent-scavenging agent system, are converted to voluminous masses of fibrous metal product. Studies have been carried out to determine the conditions which lead, on the one hand, to irregular poly crystalline fibers and, on the other, to long single crystal filaments a few microns in diameter. A mechanism is proposed to account for the formation of single crystal filuments. The sulfide minerals of Cu, Ni, Co, and Fe are an important source of these metals yet there has been comparatively little scientific effort devoted towards understanding reduction mechanisms of these minerals. This may be, in part, due to the fact that the most convenient reducing agents for carrying out such studies, viz., hydrogen and carbon, do not react appreciably with sulfides. We have found that the reaction of hydrogen with metal sulfides can be markedly accelerated by placing a scavenging agent for hydrogen sulfide in close proximity to the metal sulfide. A brief series of experiments demonstrating relative reduction rates is reported in this paper to illustrate the effect. With the reduction process thus accelerated we have observed an unusual type of reduction behavior on some of the sulfides investigated. Under certain conditions the metallic product of the reduction reaction takes the form of filaments growing outward from the sulfide particles. The present paper deals largely with efforts to classify the various types of growth forms observed. This study has shown that filamentary growths from sulfides take a much greater variety of forms than has heretofore been reported by Ercker,1 Hardy,2 and Nabarro and Jackson3 in their reviews of metallic growths from copper and silver sulfides. THERMODYNAMIC CONSIDERATIONS The thermodynamics for hydrogen reduction of metal sulfides is quite unfavorable. For the sulfides considered here equilibrium constants typically range from 10-3 to 10-5. These low equilibrium constants impose severe kinetic limitations on reduction since hydrogen sulfide must be transported out of the system at concentrations of only a few hundred ppm. Unless extremely high gas flow rates are employed the atmosphere surrounding any sulfide particle will always be essentially in equilibrium with the sulfide. If, however, one places an efficient scavenging agent for hydrogen sulfide in close proximity to the metal sulfide particles the concentration of H2S near the metal sulfide will be held to a very low value. This would permit the reduction reaction to proceed with little or no inhibition from a buildup of reaction product gas. It is well known that calcium oxide is capable of removing hydrogen sulfide from a hydrogen gas stream of low dew point.4 If a sufficient quantity of calcium oxide is mixed with the metal sulfide particles the reaction: CaO+H2S=CaS+ H2O [l] will substitute moisture in place of hydrogen sulfide in the gas stream and this will not affect, in a direct manner, the reaction: MeS +H2=Me + H2S [2] A convenient method of considering the thermodynamics of the combined reducing agent-scavenging agent system is to consider the atmosphere when the partial pressure of hydrogen sulfide is the same over both the metal sulfide and the scavenging agent, i.e., pH2S (1) =pH2S (2). As a consequence: pH2O (1) pH2(2) =K1K2 The chemical driving force for reduction will depend inversely upon the moisture content of the gas and will be 0 when, in the system, pH2O = pH2.K1K2. Table I lists values of the equilibrium constants for reduction and H2S scavenging reactions for a number of sulfides at several temperatures. Data are taken from Rosenqvist4,5 and Kelly.6 The equilibrium constant products calculated from this data show that the limiting level of gaseous reaction product has been increased by a factor of 10' to l04 as a result of substituting a reducing agent-scavenging agent system for a simple reducing agent system. One possible side effect which must be considered is the possibility that the moisture evolved in the scavenging reaction might cause the atmosphere in the system to be sufficiently oxidizing to favor the formation of oxide rather than metal. This possibility was examined by comparing the equilibrium constant products listed in Table I with equilibrium constants for hydrogen reduction of the respective metal oxides. It was found that for copper, nickel, and cobalt the combined reduction-scavenging reactions could not develop a sufficiently high oxidizing potential in the

Jan 1, 1970

By B. B. Zavoico

The oil industry in the Soviet Union closed the 1929-1930 operating year fulfilling its assigned program. During this period of time, however, no basic improvements were noted within the industry. A careful study of the conditions indicates that disorganization in most branches increased continually; that supply and transportation problems are approaching a state of breakdown; that labor problems become increasingly difficult and that the estimates for 1931-1933 period are too large. The production of all Russian fields increased by 27,200,000 bbl., as compared with the 1928-1929 operating year, while the next year's program anticipates a further increase of 46,000,000 bbl., and the 1933 plans call for an amazing total of 330,000,000 bbl., or over 150 per cent, more than the production of the operating year that has just closed. Table 1 shows petroleum production in Russia by individual areas and fields from 1916, and furnishes estimates for the three coming years, which constitute the balance of the Five-year plan. A brief analysis of Table 1 will show that the Soviet Planning Commission anticipates that the fully developed fields of the Apsheron-Baku will double their production by 1933, .as compared with 1929-1930, and that the old Grozny fields, which are already showing a tendency to decline, will increase their output from 44,110,000 bbl. in 1929-1930 to 68,000,000 bbl. in 1933. Furthermore, in 1933 new fields are slated to produce not less than 100,000,000 bbl., a figure which even under most favorable conditions in Russia would be hard to achieve. Of course, Russia could develop such production, because the country is not lacking in the prospective reserves, but the transportation in the country today (as in the past.) is in such poor shape that neither the supply of a gigantic oil industry nor the movement of its products is within the realm of possibility. Table 1 shows the future estimated crude oil production as required by the Five-year plan, and also as reasonably estimated by the author, taking into account natural declines in old fields, slow development of new areas and the deficiency of the transport. While in the 1929-1930 operating year only two major fields underproduced (Surakany and Maikop) and the plan was fulfilled to the extent of 97.4 per cent., the production of the last three months of 1930 ("Shock Quarter") indicated

Jan 1, 1931

By J. W. Richards

Plating iron with copper has received great attention from practical and scientific men, but, aside from the deposit secured by immersion of iron in copper salts, by electro-plating, or by welding together thin sheets of iron and copper, these efforts have met with no success. Failure of these efforts, in the production of copper plating, has been due to the fact that the conditions normally and necessarily present in the plating operation are antagonistic to the production of copper-plated iron. In most, if not quite all of them, a bath of molten copper has been used. The temperature of a molten copper bath is so high that the iron becomes oxidized before it can be immersed in the molten copper, and unless a protective flux for the molten copper is used, the surface of the copper will become oxidized, and, in any event, the plated iron will oxidize immediately on its being withdrawn from the molten bath. I recently had the pleasure of visiting the works of The Metals Plating Co. at Elizabeth, N. J., where I witnessed the plating of iron sheets with copper by a new process.l The plating metal is applied to the sheet in the form of a liquid mixture by means of rolls, such as inking rolls. The sheet, after being coated with the mixture, is automatically carried forward and deposited on a link-belt conveyor, which carries it through a furnace maintained at a temperature well above that of molten copper. The basic principle involved in this method lies in the application of the plating metal to the sheet while the sheet is cold and then melting the metal in place on the sheet under conditions which are favorable to the formation of the plating. Plating Mixture The liquid plating mixture is composed of either copper oxide or finely divided copper, or a mixture of both, ground to the consistency of a light varnish in a crude oil having an asphaltic base, of a specific gravity of from 14" to 16' Be. The plating mixture which gives the best results

Jan 1, 1919

By H. F. McCullough

THE success of a coal-mining venture as relates to operations at the gob or break-line, such as the drawing of pillars or the working of long-faces, depends upon the control of face conditions. The measures required to control the latter are dependent upon the action of the coal seam, roof and floor at and in the vicinity of the faces, but the manner in which these will act is dependent upon the rate of face movement as well as upon the face characteristics and upon the forces exerted. Yet the merits of a method of working-the practicability of controlling face conditions and the means required for such control when applied to any particular case-are usually judged only upon a consideration of the characteristics of coal seam, roof and floor, and the manner in which they have been observed to act. Practically every coal-mining man knows that face conditions are influenced by the rate of face movement, but few have appreciated that this is as much of a factor in the control of face conditions as are the face characteristics and the forces exerted. Fewer yet have recognized or taken advantage of faster rates of face movement as one of the principal means of establishing control of face conditions or of securing more favorable face conditions. Seemingly inherent difficulties, particularly in the control of roof conditions, but also in the control of conditions of the coal seam and floor, are frequently mitigated or disappear when the rate of movement of the faces is sufficiently increased. The characteristics of the coal seam, roof and floor and the forces exerted upon them do determine the general trend or tendency of face action, but the manner in which the coal seam, roof and floor will act and be acted upon and the magnitude of the action during the time the site of mining operations remains at any particular point is very largely determined by the rate of movement of the faces.

Jan 10, 1926

By H. Landsberg

IN a previous report1 it was pointed out that a successful attack on roof troubles has to be preceded by extensive scouting. As Lord Kelvin once said, scientific progress can be made only if accurate data are available: "unless you measure, you do not know.? THE CONVERGENCE RECORDER For the observation of roof movements in mines the convergence recorder has shown that it will enable us to get some of the necessary information. Results with convergence recorders were first published by Winstanley and other English investigators for rapidly moving longwall faces. In their investigations the speed of work and the heavy over-burden produced a considerable amount of absolute values of convergence in a short time. Under the conditions frequently encountered in our investigations in Central Pennsylvania, under shallow, overburden and in mines with slowly proceeding extraction, the movements observed were much less in absolute value, for an equal interval of time. This was partly because the mines in which our studies were carried on frequently had idle days, sometimes four or five in succession. Therefore continuous records were not employed and a simple convergence gauge was built. In its first models, it consisted only of two telescoping tubes pressed against roof and floor by a coil spring. At the side of the lower tube a rule divided into 1/-mm. divisions was fixed and a knife-edge, which was attached to the upper tube, was slid over the scale in case of convergence between roof and floor. While the larger motions could be read on this device, it seemed to be desirable to increase the accuracy by inserting between the two tubes a dial meter reading in 1/1000 in. Such a gauge was first built in April 1937 and installed for experimental purposes in a bituminous coal mine in Pennsylvania (Fig. 1). It was read at least once daily, 24 hr. apart, and if feasible at shorter intervals. After several months of experience it can be said that this type of gauge answers the scientific as well as the practical needs. It is easier to handle than the recorder; no clock is used, there are no pen troubles. The price of

Jan 1, 1938

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Jan 1, 1907

PRESIDENTS DAVID THOMAS 1871 R W RAYMOND 1872-1874 A L HOLLEY1875 ABRAM S HEWITT 1876 T STERRY HUNT 1877 ECKLEY B COXE 1878 - 1879 WILLIAM P SHINN 1880 WILLIAM METCALF 1881 RICHARD P ROTHWELL 1882 ROBERY W HUNT 1883 JAMES C, BAYLES 1884-1885 ROBERT H RICHARDS 1886 THOMAS EGLESTON 1887 WILLIAM B POTTER 1888 RICHARD PEARCE 1889 ADAM S HEWITT 1890 JOHN BIRKINBINE 1891-1892 H M HOWE 1893 JOHN FRITZ 1894 J D WEEKD 1895

Jan 1, 1923

Jan 1, 1940

Jan 1, 1970

By O. O. Laudig

It is a well-established fact that some ores do not reduce as readily in the furnace as others, thus seriously affecting out-put, and consequently, cost of product. With the object of obtain ing some information upon this subject, the following experi ments were made in the laboratory of the Buffalo Furnace Company. Efforts were made to obtain, as nearly as possible, represent ative ores from some of the most important mining districts in the United States. The ores received were from the Mesabi, Marquette, Gogebic, Menominee and Vermilion ranges of the Lake Superior district and from Southwest Virginia. Requests

Jan 1, 1897

By C. Baldwin Sawyer

During the last half century, much time has been devoted to investigations of the effect of nitrogen on the physical properties of steel, but in all discussions of results there is considerable doubt as to the accuracy and interpretation of analyses. No conclusions concerning the effects of nitrogen on the physical properties of steel can be more reliable than the methods used for determining the quantities of nitrogen present. The work described in this paper endeavors to establish some additional conditions required by the customary distillation method for reliable and nccurate determinations. Results by a combustion method of analysis for total nitrogen content are presented; these indicate that all of the nitrogen in steel, exclusive of that contained in blowholes, may be determined by the distillation method. Based on these more sound and more reliable analyses, results havc been obtained that bear on the following divisions of the general subject, nitrogen in steel: Nitrification of steel by melting in nitrogen, nitrification of steel by heating in ammonia, decomposition of nitrified steel by heating, and thermal analysis of nitrified steel. Consideration of Two Methods of Analysis and Some Results The details of the distillation and combustion methods are chemical in character and of little interest to most readers. They are therefore described in an appendix. The distillation method is essentially that described by Hurum and Fay1 and was generally used throughout this work. It is capable of the greatest accuracy and all results given are significant to the last, figure. Where analyses do not check, the samples

Jan 1, 1923

By R. T. Webber, B. B. Owen

THE vapor phase deposition of molybdenum and tungsten from the hexacarbonyls has been thoroughly investigated by Lander and Germer1 and shown to yield well-bonded coatings on a variety of hot metallic surfaces. They also demonstrated that chromium coatings2.3 could be similarly deposited, but did not investigate this metal extensively. Recently,4 conditions have been described by which this compound can be prepared in quantities sufficient for laboratory scale plating experiments, and it is the purpose of the present communication to outline the results of preliminary experiments upon the plating of chromium from its carbonyl. APPARATUS AND TECHNIQUE The apparatus used in these experiments is shown in Fig I. At one end, connected by a short length of rubber tubing, is a Cenco Hypervac 20 pumping continuously. At the opposite end is a needle valve which allows a small stream of purified hydrogen to flow through the apparatus. Connected in series are a trap T1, maintained at the temperature of dry ice and acetone, the plating chamber, and two traps T2 and T3 containing crystals of the carbonyl. T2 is kept in a constant temperature bath (not shown), while T3 is at room temperature. Stopcock S6 allows the hydrogen flow to by-pass the carbonyl traps. A McLeod gauge is connected so that it can measure the pressure at the pump through Ss, or the pressure at the plating chamber through S9 and S6. The standard (12 liter) volume connected by S5 is used to determine the volume included by S4, S6, Se, S10, the needle valve and the McLeod gauge. Knowledge of this volume allows calibration of the flow of hydrogen. The apparatus* is built entirely of pyrex, except for the needle valve, the rubber connection to the Hypervac, and the cover of the plating chamber. The plating chamber is water-jacketed, with a large brass top allowing insertion of the specimen to be plated. Set into the brass top is a ground glass stopper through which thermocouple leads are sealed. The thermocouple wires (pure Pt, and 87 pct Pt-13 pct Rh) serve the double purpose of measuring the specimen temperature and suspending it in the chamber. Surrounding the chamber is the coil of an induction heater, H. The apparatus is designed to allow variation of the following conditions: I, the specimen temperature, from room temperature to about 1000°C, 2, the carbonyl vapor pressure, from 40 to 220 microns, and 3, the hydrogen flow. In several runs, 0.8 to 1.8 pct of hydrogen sulfide was introduced through a needle valve that replaced S4. The vapor pressure of the carbonyl is

Jan 1, 1948

By Louis Stott

IT is well known that the oxide of beryllium was identified as a new "earth" in 17971 and the metal first isolated in 18272. The history of the many difficulties encountered by early investigators, the laboratory achievements of Lebeau3, Fichter4 and Oesterheld5, and the eventual development of methods for commercial production are well covered in the literature, particularly in the authoritative published work of Siemens and Halske6 reviewing their comprehensive investigation of the element. Accordingly it has seemed desirable to restrict this paper to the properties and uses of beryllium and its alloys.

Jan 1, 1936